diff options
Diffstat (limited to 'net/sunrpc/cache.c')
| -rw-r--r-- | net/sunrpc/cache.c | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 12bb23b8e0c5..a349094f6fb7 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * net/sunrpc/cache.c * @@ -5,9 +6,6 @@ * used by sunrpc clients and servers. * * Copyright (C) 2002 Neil Brown <neilb@cse.unsw.edu.au> - * - * Released under terms in GPL version 2. See COPYING. - * */ #include <linux/types.h> @@ -40,6 +38,7 @@ static bool cache_defer_req(struct cache_req *req, struct cache_head *item); static void cache_revisit_request(struct cache_head *item); +static bool cache_listeners_exist(struct cache_detail *detail); static void cache_init(struct cache_head *h, struct cache_detail *detail) { @@ -54,6 +53,7 @@ static void cache_init(struct cache_head *h, struct cache_detail *detail) h->last_refresh = now; } +static inline int cache_is_valid(struct cache_head *h); static void cache_fresh_locked(struct cache_head *head, time_t expiry, struct cache_detail *detail); static void cache_fresh_unlocked(struct cache_head *head, @@ -105,6 +105,8 @@ static struct cache_head *sunrpc_cache_add_entry(struct cache_detail *detail, if (cache_is_expired(detail, tmp)) { hlist_del_init_rcu(&tmp->cache_list); detail->entries --; + if (cache_is_valid(tmp) == -EAGAIN) + set_bit(CACHE_NEGATIVE, &tmp->flags); cache_fresh_locked(tmp, 0, detail); freeme = tmp; break; @@ -303,7 +305,8 @@ int cache_check(struct cache_detail *detail, cache_fresh_unlocked(h, detail); break; } - } + } else if (!cache_listeners_exist(detail)) + rv = try_to_negate_entry(detail, h); } if (rv == -EAGAIN) { @@ -370,7 +373,7 @@ void sunrpc_init_cache_detail(struct cache_detail *cd) spin_lock(&cache_list_lock); cd->nextcheck = 0; cd->entries = 0; - atomic_set(&cd->readers, 0); + atomic_set(&cd->writers, 0); cd->last_close = 0; cd->last_warn = -1; list_add(&cd->others, &cache_list); @@ -1026,11 +1029,13 @@ static int cache_open(struct inode *inode, struct file *filp, } rp->offset = 0; rp->q.reader = 1; - atomic_inc(&cd->readers); + spin_lock(&queue_lock); list_add(&rp->q.list, &cd->queue); spin_unlock(&queue_lock); } + if (filp->f_mode & FMODE_WRITE) + atomic_inc(&cd->writers); filp->private_data = rp; return 0; } @@ -1059,8 +1064,10 @@ static int cache_release(struct inode *inode, struct file *filp, filp->private_data = NULL; kfree(rp); + } + if (filp->f_mode & FMODE_WRITE) { + atomic_dec(&cd->writers); cd->last_close = seconds_since_boot(); - atomic_dec(&cd->readers); } module_put(cd->owner); return 0; @@ -1168,7 +1175,7 @@ static void warn_no_listener(struct cache_detail *detail) static bool cache_listeners_exist(struct cache_detail *detail) { - if (atomic_read(&detail->readers)) + if (atomic_read(&detail->writers)) return true; if (detail->last_close == 0) /* This cache was never opened */ @@ -1372,7 +1379,6 @@ static void *cache_seq_next(struct seq_file *m, void *p, loff_t *pos) hlist_first_rcu(&cd->hash_table[hash])), struct cache_head, cache_list); } -EXPORT_SYMBOL_GPL(cache_seq_next); void *cache_seq_start_rcu(struct seq_file *m, loff_t *pos) __acquires(RCU) @@ -1518,6 +1524,9 @@ static ssize_t write_flush(struct file *file, const char __user *buf, cd->nextcheck = now; cache_flush(); + if (cd->flush) + cd->flush(); + *ppos += count; return count; } |